Yarn-feeding mechanism for knitting machines



Feb. 4, 1930. M. c.- MILLER YARN FEEDING MECHANISM FOR KNITTING MACHINESFiled Dec. 6, 1924 Ill-i INVENTON, I

Patented Feb. 4, 1930 PATENT FFICE.

MAX C. MILLER, 01 CUMBERLAND, RHODE ISLAND YABN-FEEDING MECHANISM FORKNITTING MACHINES Application filed December 6, 1924. Serial No.754,362.

The invention relates to yarn feeding mech anism for knitting machinesand has to do particularly with machines that produce fabric by relativereciprocation of the needle bed 5 0r cylinder and the cams or deviceswhich form the knitting wave to which the yarn is fed by the yarn eye oreyes.

Machines of this type may be flat or circular and the relativereciprocation between the needles and the yarn feeding and cam elementsmay be eifectedby reciprocation of the knitting cams and yarn eye or ofthe needle supporting bed or cylinder. I

On machines upon which fabric is produced through a reciprocation. ofeither the cam elements or' the needle support, it is customary tocontinue the stroke of-the reciprocating elements until the cam elementshave cleared the active needles anduntil the yarn feeding element haspassed beyond thelast active needle a sufiicient distance to insure thelast needle getting its yarn. This necessitates the use of take-ups, onefor each yarn being used, in order that the surplus slack yarn betweenthe yarn feeding element and the last active needle may be taken upduring the relative reciprocation between the needles andthe cam andyarn feeding elements. The use of such take-ups is objectionable sincethey limit the speed at which the machine may be operated and'alsorequire the use of a high grade of yarn which will stand the strain ofthe take-up action. Their use is also objectionable since they cause thelast needle or needles knitting in anygiv'en stroke to knit loops of asize differing from those knit by the needles more centrally located inthe series of active needles, such difference in' the size of the loopsbeing due to the varying tension placed upon the yarn by the action ofthe take-up. g

The use of take-ups is particularly objectionable on double bankstraight barmachines 6f the Lamb or Burson type which are de-, signed toknit tubular fabric, since they render it extremely difficult and, onfine gauges, practically impossible, to knit the'end needle loops of thesame length and appearance as.

the loops in the parts of the fabric knit by the more central needles ofthe knitting serles. t

It is the primary-object of the present invention to provide a yarnfeeding mechanism for machines operating either wholly or in part toproduce the fabric by relative re ciprocation of the needles and camelements which causes a knitting wave to travel back and forth along asingle or double series or bank of needles. It is a further object of cothe invention to provide a mechanism of this character which is welladapted for application to a double bank straight bar machine of .thetype above referred to although it wouldbe-understood that the inventionis not as confined in its application to this type of machine.

To these ends the invention comprises the features of construction andcombination of parts hereinafter described and specified in the claims.

In the'drawings one embodiment of the invention is shown applied to adouble bank straight bar machine adapted for knitting either fiat ortubular fabric. In these drawings Figure 1 is a transverse sectionalview showing somuch of the machine of this typeas is necessary toillustrate the application of the present invention thereto; Fig. 2 is apartial elevation looking toward the left in Fig. 30 1, the right handneedle bed and parts supported thereby as well as the web holders beingomitted for the sake of 'clearness; Fig. 3 is a partial plan view ofparts illustrated in Fig. 1; and Fig. 4 is a view in side elevation ofthe parts shown in Fig. 1 looking towards the right.

In the machine illustrated in the drawings, two series of banks ofneedles are supported and guided in the two opposed needle beds 1 whichare or may be of the usual construe v tion. The knitting wave which, inknitting tubular fabric, travels along one bank in one direction andback across the other bank in the opposite direction and which inknitting fiat fabric travels back and forth along one of the banks, isformed bythe usual cam elements comprising the needle advancing cams 9,9 which may be rendered alternatively active or inactive and the stitchcam 8, these cam elements being carried,as is usual,by cam bars 6mounted to slide in cam slide bearings 2 secured to the needle beds.vertically reciprocating web holders which form no part of the presentinvention are indicated at 1A.

The mechanism for feeding the yarn or yarns to the needles 'comprises ayarn finger 4' provided with one or more guides or thread eyes fordelivering the yarn to the needles of the knitting wave, two such threadguides'or eyes being indicated at 4 relatively arranged for plaitin Theyarn finger is provided with avertlcal shank mounted torotate in abearing in the yarn carrier 4' about a vertical axis located in thecenter line of the machine midway between the needle beds: The yarncarrier 4 is mounted to slide on a cylindrical bar or rock shaft 3 whichis mounted in brack- 'ets 2A formed on the cam slidebearings ,2.

The yarn carrier is provided with a lug 4 resting on one of a pair ofcylindrical bars or rock shafts 11 {which are mounted in the brackets2Aabove the needle bed. The yarn finger may be turned through an angleof- 180 degrees to bring the yarn eyes into position'to deliver the yarnto either one or the other bank of needles by means of a rack 4mounted-in the upper end of the yarn finger bearing and provided withrack teeth engaging teeth formed on the upper end of the yarn fingershank.' The rack may be shifted'to shift the yarn carrier from one sideto the other by means oftwo bars 10 extending longitudinally of themachine and carried upon arms 12 the engagement of a plate 7 carried bythe cam slides 6 and arran ed to engage a latch lever 5 which'is pivotedat 5 on the yarn carrier and is held 1n engagement with the bar 3 by aspring 5 connecting it with a finger'depending from the yarn carrier.The spring. not only holds .the latch in engagement with the bar 3, butalso holds the lug 4 of the yarn carrier in {engagement with the lefthand bar 11. The latch-5 is V-shaped at 5 -to engage notches 39 formedin the bar 3. f

The operation is as follows: As shown in Figs. 1 and 2, the yarns arebeing fed to'the left hand bank of needles and the lever 3A which issecured to the end of the bar 3 is'in the full line position marked X sothat the notches 3 willbein position to be engaged [by the latch 5. Thenotches are located in such position that they will be engaged by thelatch 5 when the thread eyeshave passed beyond the last active needleand is located beend of the active series, or in case the last activeneedle is the end needle of the series, at a distance beyond this needlesubstantially one half the gauge 'or distance between two needles. Whenthe latch 5 reaches the notch 3 at the left, it enters the notcli,thereby a swin 'n into the dotted line pos1t1on of Fig.

1 an disengagin itself from the plate 7 so that the travel 0 the threadfinger is accurately and positively arrested in a definite position withthe yarn-eye or eyes just beyond the last activeneedle or between it andthe adjacent inactive needle. The travel of the cam slide. 6 continuesto complete the travel of the stitch cam and knitting wave across theseries of active needles and to carry the inactive needle elevating cams9 to a position clear of the needles. During this continued travel ofthe stitch cam, the needles near the end of the series draws the yarnwhich was delivered to them by the yarn eyes before the were arrested bythe engagement of the late 5 with the notch 3". The continued travel ofthe cam slide after the thread finger has been arrested carries theplate 7 beyond the latch 5 to the left-so that it is in position to acton the latch during the return stroke of the slide toward the right.Before the plate 7 reaches the latch in the return stroke of the camslide, the bar 3 is rocked into theposition indicated at Y, Fig. 1, bypattern mechanism acting through a link 3 connected with the arm 3A onthe end ofthe' bar. This movement of the har'swings thelatch into fullline position and into the path ofthe plate 7 so that the return travelof the thread finger is started when the knitting wave formed by the nowactiveneedle raising cam 9* and stitch cam 8 has reached the properrelation with the thread finger. The thread finger now travels towardthe right along the series of active needles with the knitting the latch5 reaches the notch 3" wave until at the right,

the bar 3 in the meantime havmg vbeen returned to the position indicatedat X in-Fig. ,and' then the latch enters this notch and arrests thetraverse of thethread finger and holds it in definite position while thecam slldes complete their stroke to the right.

In case a fiat fabric is bein left bank, of needles, the yarn fingerwill reknit en the main in the position indicated in Fig. 1 with i theyarn eyes in position to feed their yarns to this series of needles. Ifa tubular fabric is being knit, the thread finger will be swing throughan angle of 180 degrees after the stitch cam has assed beyond the activeneedles. This wilFbring the eyes into position to deliver their arms tothe needles in the right hand or ront bank and durin stroke of theea'mslides toward the rig t needle raising cam 9 for the right orfrontbank will be rendered active to cause the knitthe the ting waves totravel toward the right along the frontbank. At the end of the stroke inthis direction, the thread finger will be swungbackwards tothe'positionindicated in Fig. 1 to deliver its yarns to a knitting wave formed inthe-left handor rear bank during the sucpegiing stroke of the cam slidestoward the e In either case, thatis, whether knitting flat or tubularfabric, the re will be no surplus slack yarn between the yarn eye oreyes and the end needle of the active series at the completion of thestroke of the reciprocating element .or after the knitting wave hascompleted its traverse along the needles and the yarns maybe uniformlyand accurately fedto all the needles under even tension and in suchmanner that the needlesthroughout the active series whatever itslengths, may draw uniform orthe desired length of loops and thus afabric produced having the desired and predetermined characteristicsthroughout.

As shown in Fig. 2,the lines W indicate the last needles in the needlebeds and the notches 3 in the bar 3 are located just beyond theseneedles. It will be understood, however, that the bar may have a numberof sets of notches,

any set of whichmay be brought into active relationwith the latch 5 byrotation or adjustment-of the bar as, for instance, by shifting it inthe arm 3" or by proper action of the pattern mechanism. These notchesmay be arranged to positively stop the relative traverse of the yarneyes along the needles at any desired point and the points of stoppingmay be varied at different strokes as, for instance, in knitting-anarrowed or widened fabric.

While the invention has been shown emneeclle machine in which thetraverse of the knitting wave and am eye relative to the needles iseffected y reciprocation of the knitting cams and yarn eye, and in whichthe traverse of the yarn eye relative tothe needles is arrested byarresting the movement of the yarn eye, it will be understood that the"invention is not confined in its application to this type securing thetraverse of the knitting wave and yarn eye or to this manner ofarresting the traverse of the eye relative to the needles. For instance,if the broader features of the invention were to be embodied in amachine in which the traverse of the knitting wave and thread eye alongthe needles is secured by reciprocation of the needles rather than ofof-machine or to this manner of 1. In a straight knitting machine thecombination with a bank of needles, and a reciprocatiugcam slide, of ayarn carrier, a latch on the carrier, a guide bar on which the carrierslides, and notches in the bar with which the latch engages to arrestthe movement 'of the carrier and means for disengaging the latch fromthe notches. v

2. .In aknitting machine, the combination with a bank of needles, of ayarn carrier movable back and forth across the needles, a re ciprocatingslide, alatch on the carrier for connecting the carrier and slide, astop to engage the latch and stop the carrier during the continuedmovement of the slide, and means for moving the latch to release theslide and engage the stop.

3. In a knitting machine the combination of a bank of needles, of a yarncarrier movable back and forth across the needles, a latch on thecarrier, a slide provided with a plate to engagethelatch, a stop toengage the latchand stop the carrier during the continued movement ofthe slide, and means for moving the latch to release the slide andengage the stop. 1

4. In a knitting machine the combination with a bank of needles, of ayarn carrier mov- .able back and forth across the needles, areciprocating slide, a latch on the carrier forming an-abutment to beengaged by abutments on the slide, stops to engage the latch and stopthe carrier during the continued movement of the slide in eachdirection, and'means I for moving the latch to release the slide andengage-the stops.

5. In a knitting machine the combination v with a bank of needles, of ayarn carrier movbodied 1n a double bank straight bar latch able backand.forth across the needles, areciprocating slide, a latch on the carrierforming an abutment to be engaged by abutments on the slide, a barprovided with notches with which the latch engages to arrest themovement of the carrier and'release the slide, and means for moving thebar to disengagethe latch from the notches and move the latch into slideengaging position; I

6. Ina knitting machine the combination with a bank of needles, of ayarn carrier movable back and forth across the needles, a reciprocatingslide, a latch on'the carrier for connecting the carrier and slide,a barpro.- vided with notches with which the latch engages to arrest themovement of the carrier and release the slide, and means for rocking thebar to disengage the latch from the notches. I

In testimony whereof I have signed my name to this specification. I

M C. MILLER.

